Karnataka is rushing Rs 10 crore worth relief materials to the neighbouring flood-hit Kerala following heavy monsoon rains, said an official statement on Thursday.

"Chief Minister H.D. Kumaraswamy directed state Chief Secretary T.M. Vijaya Bhaskar to rush relief materials and a team of doctors to Kerala, reeling under heavy rains and flash floods," said the statement.

On Kerala's request, the state government has also agreed to release 75,000 cusecs of water from Kabini reservoir in Mysuru districts to tackle the flash floods caused by excessive backwaters across the border in Kerala.

One of the tributaries, Kabini, originates in the Waynad district and flows eastward to join the Cauvery river at T. Narasipura in Karnataka.

"Kumaraswamy also called on his Kerala counterpart Pinarayi Vijayan and discussed the flood situation in that state. He also offered more relief material and aid to the affected people across the state," added the statement.

He further requested chief secretaries in the state to immediately release the relief material.

The death toll in rain-related incidents rose to 26, with large-scale damage reported from various parts of Kerala.

Idukki, Malappuram, Palghat, Kozhikode, Wayanad and parts of Kannur are the worst-affected districts in coastal and north-eastern areas of Kerala.

One hundred control rooms have been opened in flood-hit districts in the state while relief camps were opened in Thiruvananthapuram, Alappuzha, Idukki, Ernakulam, Thrissur, Palakkad, Malappuram, Kozhikode, Wayanad and Kannur.

The unprecedented rains in the district have also forced the state government to open the gates of the Idukki dam for the first time in 26 years.

Heavy rains also lashed Kodagu and parts of Mysuru district of Karnataka. Authorities issued a flood alert for Mysuru while heavy vehicles were restricted from plying on the Madikeri-Mangaluru highway.